A. Background Regarding Nanoparticulate Compositions
Nanoparticulate compositions, first described in U.S. Pat. No. 5,145,684 (“the '684 patent”), are particles consisting of a poorly soluble active agent having adsorbed onto the surface thereof a non-crosslinked surface stabilizer. The '684 patent also describes methods of making such nanoparticulate compositions. Nanoparticulate compositions are desirable because with a decrease in particle size, and a consequent increase in surface area, a composition is rapidly dissolved and absorbed following administration. Methods of making such compositions are described in U.S. Pat. Nos. 5,518,187 and 5,862,999, both for “Method of Grinding Pharmaceutical Substances,” U.S. Pat. No. 5,718,388, for “Continuous Method of Grinding Pharmaceutical Substances;” and U.S. Pat. No. 5,510,118 for “Process of Preparing Therapeutic Compositions Containing Nanoparticles.”
Nanoparticulate compositions are also described in, for example, U.S. Pat. No. 5,298,262 for “Use of Ionic Cloud Point Modifiers to Prevent Particle Aggregation During Sterilization;” U.S. Pat. No. 5,302,401 for “Method to Reduce Particle Size Growth During Lyophilization;” U.S. Pat. No. 5,318,767 for “X-Ray Contrast Compositions Useful in Medical Imaging;” U.S. Pat. No. 5,326,552 for “Novel Formulation For Nanoparticulate X-Ray Blood Pool Contrast Agents Using High Molecular Weight Non-ionic Surfactants;” U.S. Pat. No. 5,328,404 for “Method of X-Ray Imaging Using Iodinated Aromatic Propanedioates;” U.S. Pat. No. 5,336,507 for “Use of Charged Phospholipids to Reduce Nanoparticle Aggregation;” U.S. Pat. No. 5,340,564 for “Formulations Comprising Olin 10-G to Prevent Particle Aggregation and Increase Stability;” U.S. Pat. No. 5,346,702 for “Use of Non-Ionic Cloud Point Modifiers to Minimize Nanoparticulate Aggregation During Sterilization;” U.S. Pat. No. 5,349,957 for “Preparation and Magnetic Properties of Very Small Magnetic-Dextran Particles;” U.S. Pat. No. 5,352,459 for “Use of Purified Surface Modifiers to Prevent Particle Aggregation During Sterilization;” U.S. Pat. Nos. 5,399,363 and 5,494,683, both for “Surface Modified Anticancer Nanoparticles;” U.S. Pat. No. 5,401,492 for “Water Insoluble Non-Magnetic Manganese Particles as Magnetic Resonance Enhancement Agents;” U.S. Pat. No. 5,429,824 for “Use of Tyloxapol as a Nanoparticulate Stabilizer;” U.S. Pat. No. 5,447,710 for “Method for Making Nanoparticulate X-Ray Blood Pool Contrast Agents Using High Molecular Weight Non-ionic Surfactants;” U.S. Pat. No. 5,451,393 for “X-Ray Contrast Compositions Useful in Medical Imaging;” U.S. Pat. No. 5,466,440 for “Formulations of Oral Gastrointestinal Diagnostic X-Ray Contrast Agents in Combination with Pharmaceutically Acceptable Clays;” U.S. Pat. No. 5,470,583 for “Method of Preparing Nanoparticle Compositions Containing Charged Phospholipids to Reduce Aggregation;” U.S. Pat. No. 5,472,683 for “Nanoparticulate Diagnostic Mixed Carbamic Anhydrides as X-Ray Contrast Agents for Blood Pool and Lymphatic System Imaging;” U.S. Pat. No. 5,500,204 for “Nanoparticulate Diagnostic Dimers as X-Ray Contrast Agents for Blood Pool and Lymphatic System Imaging;” U.S. Pat. No. 5,518,187 for “Method of Grinding Pharmaceutical Substances;” U.S. Pat. No. 5,518,738 for “Nanoparticulate NSAID Formulations;” U.S. Pat. No. 5,521,218 for “Nanoparticulate Iododipamide Derivatives for Use as X-Ray Contrast Agents;” U.S. Pat. No. 5,525,328 for “Nanoparticulate Diagnostic Diatrizoxy Ester X-Ray Contrast Agents for Blood Pool and Lymphatic System Imaging;” U.S. Pat. No. 5,543,133 for “Process of Preparing X-Ray Contrast Compositions Containing Nanoparticles;” U.S. Pat. No. 5,552,160 for “Surface Modified NSAID Nanoparticles;” U.S. Pat. No. 5,560,931 for “Formulations of Compounds as Nanoparticulate Dispersions in Digestible Oils or Fatty Acids;” U.S. Pat. No. 5,565,188 for “Polyalkylene Block Copolymers as Surface Modifiers for Nanoparticles;” U.S. Pat. No. 5,569,448 for “Sulfated Non-ionic Block Copolymer Surfactant as Stabilizer Coatings for Nanoparticle Compositions;” U.S. Pat. No. 5,571,536 for “Formulations of Compounds as Nanoparticulate Dispersions in Digestible Oils or Fatty Acids;” U.S. Pat. No. 5,573,749 for “Nanoparticulate Diagnostic Mixed Carboxylic Anydrides as X-Ray Contrast Agents for Blood Pool and Lymphatic System Imaging;” U.S. Pat. No. 5,573,750 for “Diagnostic Imaging X-Ray Contrast Agents;” U.S. Pat. No. 5,573,783 for “Redispersible Nanoparticulate Film Matrices With Protective Overcoats;” U.S. Pat. No. 5,580,579 for “Site-specific Adhesion Within the GI Tract Using Nanoparticles Stabilized by High Molecular Weight, Linear Poly(ethylene Oxide) Polymers;” U.S. Pat. No. 5,585,108 for “Formulations of Oral Gastrointestinal Therapeutic Agents in Combination with Pharmaceutically Acceptable Clays;” U.S. Pat. No. 5,587,143 for “Butylene Oxide-Ethylene Oxide Block Copolymers Surfactants as Stabilizer Coatings for Nanoparticulate Compositions;” U.S. Pat. No. 5,591,456 for “Milled Naproxen with Hydropropyl Cellulose as Dispersion Stabilizer;” U.S. Pat. No. 5,593,657 for “Novel Barium Salt Formulations Stabilized by Non-ionic and Anionic Stabilizers;” U.S. Pat. No. 5,622,938 for “Sugar Based Surfactant for Nanocrystals;” U.S. Pat. No. 5,628,981 for “Improved Formulations of Oral Gastrointestinal Diagnostic X-Ray Contrast Agents and Oral Gastrointestinal Therapeutic Agents;” U.S. Pat. No. 5,643,552 for “Nanoparticulate Diagnostic Mixed Carbonic Anhydrides as X-Ray Contrast Agents for Blood Pool and Lymphatic System Imaging;” U.S. Pat. No. 5,718,388 for “Continuous Method of Grinding Pharmaceutical Substances;” U.S. Pat. No. 5,718,919 for “Nanoparticles Containing the R(−)Enantiomer of Ibuprofen;” U.S. Pat. No. 5,747,001 for “Aerosols Containing Beclomethasone Nanoparticle Dispersions;” U.S. Pat. No. 5,834,025 for “Reduction of Intravenously Administered Nanoparticulate Formulation Induced Adverse Physiological Reactions;” U.S. Pat. No. 6,045,829 “Nanocrystalline Formulations of Human Immunodeficiency Virus (HIV) Protease Inhibitors Using Cellulosic Surface Stabilizers;” U.S. Pat. No. 6,068,858 for “Methods of Making Nanocrystalline Formulations of Human Immunodeficiency Virus (HIV) Protease Inhibitors Using Cellulosic Surface Stabilizers;” U.S. Pat. No. 6,153,225 for “Injectable Formulations of Nanoparticulate Naproxen;” U.S. Pat. No. 6,165,506 for “New Solid Dose Form of Nanoparticulate Naproxen;” U.S. Pat. No. 6,221,400 for “Methods of Treating Mammals Using Nanocrystalline Formulations of Human Immunodeficiency Virus (HIV) Protease Inhibitors;” U.S. Pat. No. 6,264,922 for “Nebulized Aerosols Containing Nanoparticle Dispersions;” U.S. Pat. No. 6,267,989 for “Methods for Preventing Crystal Growth and Particle Aggregation in Nanoparticle Compositions;” U.S. Pat. No. 6,270,806 for “Use of PEG-Derivatized Lipids as Surface Stabilizers for Nanoparticulate Compositions;” U.S. Pat. No. 6,316,029 for “Rapidly Disintegrating Solid Oral Dosage Form,” U.S. Pat. No. 6,375,986 for “Solid Dose Nanoparticulate Compositions Comprising a Synergistic Combination of a Polymeric Surface Stabilizer and Dioctyl Sodium Sulfosuccinate;” U.S. Pat. No. 6,428,814 for “Bioadhesive Nanoparticulate Compositions Having Cationic Surface Stabilizers;” and U.S. Pat. No. 6,432,381 for “Methods for Targeting Drug Delivery to the Upper and/or Lower Gastrointestinal Tract,” all of which are specifically incorporated by reference. In addition, U.S. patent application Ser. No. 20020012675 A1, published on Jan. 31, 2002, for “Controlled Release Nanoparticulate Compositions,” describes nanoparticulate compositions, and is specifically incorporated by reference.
Amorphous small particle compositions are described in, for example, U.S. Pat. No. 4,783,484 for “Particulate Composition and Use Thereof as Antimicrobial Agent,” U.S. Pat. No. 4,826,689 for “Method for Making Uniformly Sized Particles from Water-Insoluble Organic Compounds,” U.S. Pat. No. 4,997,454 for “Method for Making Uniformly-Sized Particles From Insoluble Compounds,” U.S. Pat. No. 5,741,522 for “Ultrasmall, Non-aggregated Porous Particles of Uniform Size for Entrapping Gas Bubbles Within and Methods,” and U.S. Pat. No. 5,776,496, for “Ultrasmall Porous Particles for Enhancing Ultrasound Back Scatter.
None of these references, or any other reference that describes nanoparticulate compositions, relates to a nanoparticulate composition having a combination of immediate release and controlled release characteristics.
B. Background Regarding Immediate Release Compositions
Conventional immediate release dosage forms, also referred to as “fast melt” or “rapidly disintegrating” dosage forms, rely on the composition of the drug matrix to effect the rapid release of the component active agent particles, rather than the particle size of the component active agent particles.
Current manufacturers of rapidly disintegrating or dissolving solid dose oral formulations include Cima Labs, Fuisz Technologies Ltd., Prographarm, R. P. Scherer, and Yamanouchi-Shaklee. All of these manufacturers market different types of rapidly dissolving solid oral dosage forms.
Cima Labs markets OraSolv®, which is an effervescent direct compression tablet having an oral dissolution time of five to thirty seconds, and DuraSolv®, which is a direct compression tablet having a taste-masked active agent and an oral dissolution time of 15 to 45 seconds. Cima's U.S. Pat. No. 5,607,697, for “Taste Masking Microparticles for Oral Dosage Forms,” describes a solid dosage form consisting of coated microparticles that disintegrate in the mouth. The microparticle core has a pharmaceutical agent and one or more sweet-tasting compounds having a negative heat of solution selected from mannitol, sorbitol, a mixture of an artificial sweetener and menthol, a mixture of sugar and menthol, and methyl salicylate. The microparticle core is coated, at least partially, with a material that retards dissolution in the mouth and masks the taste of the pharmaceutical agent. The microparticles are then compressed to form a tablet. Other excipients can also be added to the tablet formulation.
WO 98/46215 for “Rapidly Dissolving Robust Dosage Form,” assigned to Cima Labs, is directed to a hard, compressed, fast melt formulation having an active ingredient and a matrix of at least a non-direct compression filler and lubricant. A non-direct compression filler is typically not free-flowing, in contrast to a direct compression (DC grade) filler, and usually requires additionally processing to form free-flowing granules.
Cima also has U.S. patents and international patent applications directed to effervescent dosage forms (U.S. Pat. Nos. 5,503,846, 5,223,264, and 5,178,878) and tableting aids for rapidly dissolving dosage forms (U.S. Pat. Nos. 5,401,513 and 5,219,574), and rapidly dissolving dosage forms for water soluble drugs (WO 98/14179 for “Taste-Masked Microcapsule Composition and Methods of Manufacture”).
Fuisz Technologies, now part of BioVail, markets Flash Dose®, which is a direct compression tablet containing a processed excipient called Shearform®. Shearform® is a cotton candy-like substance of mixed polysaccharides converted to amorphous fibers. U.S. patents describing this technology include U.S. Pat. No. 5,871,781 for “Apparatus for Making Rapidly Dissolving Dosage Units;” U.S. Pat. No. 5,869,098 for “Fast-Dissolving Comestible Units Formed Under High-Speed/High-Pressure Conditions;” U.S. Pat. Nos. 5,866,163, 5,851,553, and 5,622,719, all for “Process and Apparatus for Making Rapidly Dissolving Dosage Units and Product Therefrom;” U.S. Pat. No. 5,567,439 for “Delivery of Controlled-Release Systems;” and U.S. Pat. No. 5,587,172 for “Process for Forming Quickly Dispersing Comestible Unit and Product Therefrom.”
Prographarm markets Flashtab®, which is a fast melt tablet having a disintegrating agent such as carboxymethyl cellulose, a swelling agent such as a modified starch, and a taste-masked active agent. The tablets have an oral disintegration time of under one minute (U.S. Pat. No. 5,464,632).
R. P. Scherer markets Zydis®, which is a freeze-dried tablet having an oral dissolution time of 2 to 5 seconds. Lyophilized tablets are costly to manufacture and difficult to package because of the tablets sensitivity to moisture and temperature. U.S. Pat. No. 4,642,903 (R. P. Scherer Corp.) refers to a fast melt dosage formulation prepared by dispersing a gas throughout a solution or suspension to be freeze-dried. U.S. Pat. No. 5,188,825 (R. P. Scherer Corp.) refers to freeze-dried dosage forms prepared by bonding or complexing a water-soluble active agent to or with an ion exchange resin to form a substantially water insoluble complex, which is then mixed with an appropriate carrier and freeze dried. U.S. Pat. No. 5,631,023 (R. P. Scherer Corp.) refers to freeze-dried drug dosage forms made by adding xanthan gum to a suspension of gelatin and active agent. U.S. Pat. No. 5,827,541 (R. P. Scherer Corp.) discloses a process for preparing solid pharmaceutical dosage forms of hydrophobic substances. The process involves freeze-drying a dispersion containing a hydrophobic active ingredient and a surfactant in a non-aqueous phase and a carrier material in an aqueous phase.
Yamanouchi-Shaklee markets Wowtab®, which is a tablet having a combination of a low moldability and a high moldability saccharide. U.S. Patents covering this technology include U.S. Pat. No. 5,576,014 for “Intrabuccally Dissolving Compressed Moldings and Production Process Thereof,” and U.S. Pat. No. 5,446,464 for “Intrabuccally Disintegrating Preparation and Production Thereof.”
Other companies owning rapidly dissolving technology include Janssen Pharmaceutica. U.S. patents assigned to Janssen describe rapidly dissolving tablets having two polypeptide (or gelatin) components and a bulking agent, wherein the two components have a net charge of the same sign, and the first component is more soluble in aqueous solution than the second component. See U.S. Pat. No. 5,807,576 for “Rapidly Dissolving Tablet;” U.S. Pat. No. 5,635,210 for “Method of Making a Rapidly Dissolving Tablet;” U.S. Pat. No. 5,595,761 for “Particulate Support Matrix for Making a Rapidly Dissolving Tablet;” U.S. Pat. No. 5,587,180 for “Process for Making a Particulate Support Matrix for Making a Rapidly Dissolving Tablet;” and U.S. Pat. No. 5,776,491 for “Rapidly Dissolving Dosage Form.”
Eurand America, Inc. has U.S. patents directed to a rapidly dissolving effervescent composition having a mixture of sodium bicarbonate, citric acid, and ethylcellulose (U.S. Pat. Nos. 5,639,475 and 5,709,886).
L.A.B. Pharmaceutical Research owns U.S. patents directed to effervescent-based rapidly dissolving formulations having an effervescent couple of an effervescent acid and an effervescent base (U.S. Pat. Nos. 5,807,578 and 5,807,577).
Schering Corporation has technology relating to buccal tablets having an active agent, an excipient (which can be a surfactant) or at least one of sucrose, lactose, or sorbitol, and either magnesium stearate or sodium dodecyl sulfate (U.S. Pat. Nos. 5,112,616 and 5,073,374).
Laboratoire L. LaFon owns technology directed to conventional dosage forms made by lyophilization of an oil-in-water emulsion in which at least one of the two phases contains a surfactant (U.S. Pat. No. 4,616,047). For this type of formulation, the active ingredient is maintained in a frozen suspension state and is tableted without micronization or compression, as such processes could damage the active agent.
Takeda Chemicals Inc., Ltd. owns technology directed to a method of making a fast dissolving tablet in which an active agent and a moistened, soluble carbohydrate are compression molded into a tablet, followed by drying of the tablets.
None of the described prior art teaches an immediate release dosage form in which a poorly soluble active ingredient is in a nanoparticulate form. This is significant because the prior art immediate release formulations do not address the problems associated with the bioavailability of poorly soluble drugs. While prior art immediate release dosage forms may provide rapid presentation of a drug, frequently there is an undesirable lag in the onset of therapeutic action because of the poor solubility and associated slow dissolution rate of the drug. Thus, while prior art immediate release dosage forms may exhibit rapid disintegration of the drug carrier matrix, this does not result in rapid dissolution and absorption of the poorly soluble drug contained within the dosage form.
C. Background Regarding Controlled Release Compositions
Controlled release refers to the release of an agent such as a drug from a composition or dosage form in which the agent is released according to a desired profile over an extended period of time. Controlled release profiles include, for example, sustained release, prolonged release, pulsatile release, and delayed release profiles. In contrast to immediate release compositions, controlled release compositions allow delivery of an agent to a subject over an extended period of time according to a predetermined profile. Such release rates can provide therapeutically effective levels of agent for an extended period of time and thereby provide a longer period of pharmacologic or diagnostic response as compared to conventional rapid release dosage forms. Such longer periods of response provide for many inherent benefits that are not achieved with the corresponding short acting, immediate release preparations. For example, in the treatment of chronic pain, controlled release formulations are often highly preferred over conventional short-acting formulations.
Controlled release pharmaceutical compositions and dosage forms are designed to improve the delivery profile of agents, such as drugs, medicaments, active agents, diagnostic agents, or any substance to be internally administered to an animal, including humans. A controlled release composition is typically used to improve the effects of administered substances by optimizing the kinetics of delivery, thereby increasing bioavailability, convenience, and patient compliance, as well as minimizing side effects associated with inappropriate immediate release rates such as a high initial release rate and, if undesired, uneven blood or tissue levels.
Prior art teachings of the preparation and use of compositions providing for controlled release of an active compound provide various methods of extending the release of a drug following administration.
Exemplary controlled release formulations known in the art include specially coated pellets, microparticles, implants, tablets, minitabs, and capsules in which a controlled release of a drug is brought about, for example, through selective breakdown of the coating of the preparation, through release through the coating, through compounding with a special matrix to affect the release of a drug, or through a combination of these techniques. Some controlled release formulations provide for pulsatile release of a single dose of an active compound at predetermined periods after administration.
U.S. Pat. No. 5,110,605 to Acharya et al. refers to a calcium polycarbophilalginate controlled release composition. U.S. Pat. No. 5,215,758 to Krishnamurthy et al. refers to a controlled release suppository composition of sodium alginate and calcium salt. U.S. Pat. No. 5,811,388 to Friend et al. refers to a solid alginate-based formulation including alginate, a water-swellable polymer, and a digestible hydrocarbon derivative for providing controlled release of orally administered compounds.
WO 91/13612 refers to the sustained release of pharmaceuticals using compositions in which the drug is complexed with an ion-exchange resin. The specific ion-exchange resin described in this published patent application is AMBERLITE IRP 69®, a sodium polystyrene sulphonate resin.
U.S. Pat. No. 5,811,425 to Woods et al. refers to injectable depot forms of controlled release drugs made by forming microencapsule matrices of the drug in biodegradable polymers, liposomes, or microemulsions compatible with body tissues. U.S. Pat. No. 5,811,422 to Lam et al. refers to controlled release compositions obtained by coupling a class of drugs to biodegradable polymers, such as polylactic acid, polyglycolic acid, copolymers of polylactic and polyglycolic acid, polyepsilon caprolactone, polyhydroxy butyric acid, etc.
U.S. Pat. No. 5,811,404 to De Frees et al. refers to the use of liposomes having prolonged circulation half-lives to provide for the sustained release of drug compositions.
Finally, WO 00/18374, for “Controlled Release Nanoparticulate Compositions,” describes controlled release formulations comprising nanoparticulate active agents.
There is a need in the art for compositions of poorly soluble drugs having a combination of immediate release and controlled release characteristics. The present invention satisfies this need.